PROPULSION UPDATE
Wichmann Reports On First Year
Of WX28 Engine Operation
Cross section of Wichmann's WX28V engine.
A/S Wichmann of Norway reported the first
WX28, a V-8 heavy-fuel engine, passed its first
12 months of operation earlier this year. The
engine, which has a maximum continuous rating
of 3,000 hp at 600 rpm, has now logged a total of
7,000 operating hours on board the M/V Bom-
meloy. In addition to the operation of the WX28
on board the Bommeloy, extensive heavy fuel
tests have been carried out on a 4-cylinder
WX28 engine on a testbed.
The operation of these two engines has
demonstrated that the WX28 satisfies the heavy
demands and stresses placed on the engine. The
prototype V-8 on board the Bommeloy has not
had any unanticipated breakdowns during its
first year of operation.
An inspection performed on the valveless-tur-
bocharged-medium-speed engine revealed prac-
tically no cylinder wear. Clean ports and a clean
combustion chamber indicated effective scav-
enging and combustion. The heavy fuel tests on
the 4-cylinder WX28L4 show cylinder wear well
below 0.02 mm per 1,000 operating hours, a wear
giving a liner lifetime of a minimum of 40,000
hours.
The WX28 has a cast iron piston skirt with a
steel piston crown. The skirt is equipped with a
shrunk-on bronze sleeve. Bronze is an excellent
bearing material, and the piston skirts look new
after one year of operation. The piston crowns
have hardened ring grooves, and the groove
height was well within the tolerances for a new
crown.
The piston is equipped with three compres-
sion rings at the upper end of the piston. Ring
No. 1 is a plasma-free-rotating ring, No. 2, a
chrome-plated-free-rotating ring, and No. 3, a
fixed-cast iron ring with a special gas-tight joint.
The ring grooves were clean upon inspection,
and there was no fouling. The ring wear on the
V-8 on board the Bommeloy was so minor accu-
rate estimates on ring lifetime are not possible.
Heavy fuel tests on the L4 indicate, however, an
interval of 8,000 operating hours between ring
renewals.
The oil scraper ring is located at the bottom
end of the piston and is working below the ports
in the cylinder liner, where the liner has no wear.
No wear was observed on these rings.
The engine has separate cylinder lubrication
from a hydraulically operated cylinder lubrica-
tor. The lubricator is essential in reducing cylin-
der and ring wear, as well as keeping them in
excellent condition.
The WX28 differs from earlier Wichmann
engines with regard to the auxiliary blower. The
engine has a fan (radial compressor) operated
hydraulically with oil from the engine's lubricat-
ing oil system. Hydraulic operation allows the
blower speed independence of engine speed,
which gives greater flexibility for adjustments.
The system has worked well and has proved reli-
able and simple.
The turbo charger, main bearings, cylinder
cover and fuel injection systems have all been
functioning excellently, both on the V-8 aboard
the Bommeloy and on the L4 on the test stand.
According to Wichmann, the first year of
operation of the WX28 has been a success. The
V-engine has had several operating profiles con-
ducted, with periods of full power, part load and
frequent maneuvering. No problems have been
reported of any kind, and inspection of the
cylinders and the pistons show a clean engine
with optimal conditions in both the cylinder and
the combustion chamber.
For further information, including a complete
detail-filled brochure,
Circle 51 on Reader Service Card
Monarch Introduces
New Pistol Grip
Portable Tachometer
Monarch Instrument of Amherst, N.H. has
introduced a new convenient non-contact op-
tical tachometer that is packaged in a pistol grip
configuration. The new instrument, called
PHASAR-TACH, measures rotational speed
over the range of 50 to 20,000 rpm to an accuracy
of +/ -1 rpm. Speeds are measured by aiming
the instrument at a single reflective marker on
the rotating object and reading the displayed
speed directly in rpm. Speeds can be measured
at distances up to three feet and angles up to 45
degrees from the reflective target.
Two models of PHASAR-TACH are avail-
able, the PHASAR-LCD featuring a liquid crys-
tal display, both equipped with an on-target
indicator. Both models are powered by four
"AA" batteries accessible by lifting the hinged
top cover of the instrument.
For those applications where the operator
needs both hands free, PHASAR-TACH may be
latched in the 'on' mode by means of a locking
push button on the pistol grip trigger, and
mounted on a standard '/J-20 threaded bushing
at the base of the handle.
For more information on the new pistol grip
tachometer from Monarch Instrument,
Circle 53 on Reader Service Card
Hydraulic Governor Valve Control
Surpasses Initial Expectations
A year after its introduction by the Power
Division of the Skinner Engine Company, Erie,
Pa., the first hydraulically actuated governor
valve control for controlling steam turbine speed
has performed even better than initial expecta-
tions. Data gathered from dozens of installations
around the country reveal a record of unsur-
passed economy, adaptability and dependabili-
ty.
The Skinner SPR™System—powered by the
Woodward TG-13 constant speed governor—
requires fewer adjustments following initial
start-up than comparable governor valve con-
trols because it is a closed system with no
mechanical wear points. It instantly corrects
variations in pre-set turbine speed without the
"hunting" for correct speed found in standard
mechanical linkage controls.
The SPR system is free from the shock loads
and backlashes which can cause the levers, arms
and pins of mechanical systems to weaken or
break prematurely. The system's elimination of
speed correction turbulence also helps extend
the life of the governor valve, cage and stem, and
the absence of any mechanical linkage reduces
maintenance costs.
At slight underspeed or overspeed conditions,
the movement of a rotary actuator in the SPR
system initiates a chain of events in the hydrau-
lic system which opens or closes the steam inlet
to provide immediate response to speed varia-
tions. The Skinner SPR system also produces a
substantial increase in the power available at
the governor valve.
The Skinner Engine Company's SPR™System is said to be
the first hydraulically actuated governor valve control for
steam turbines.
The Skinner SPR system is a retrofit package
made for all popular types of single stage steam
turbines. It is presently available in configura-
tions for Coppus, Elliot and Terry turbines with
others available upon application.
For more information and free literature on
Skinner's SPR system,
Circle 52 on Reader Service Card
46 Maritime Reporter/Engineering News
Digital Wave Publishing